Most of us know how important it is to get enough sleep – it is key for optimum brain development, learning, memory, removing toxins from cells, and the regulation of emotional, cardiovascular and metabolic systems (1). Adequate sleep is also needed for proper immune function and for recovery from exercise, especially for athletes who are looking to get stronger, faster or more agile. Sleep is essential for the repair and growth of muscles and tissues after working out.
Persistent lack of sleep, on the other hand, is strongly associated with developing obesity and a higher incidence of Type 2 diabetes, depression, heart disease, high cholesterol, high blood pressure, heart attack, stroke and hormonal or endocrine imbalances. Poor sleep can also diminish attention, memory, learning capacity, workplace productivity and academic performance (2).
Causes of insomnia
Unfortunately, many people nowadays experience difficulty in getting the quality sleep they need – from taking a long time to fall asleep, difficulty staying asleep, getting back to sleep when awakened and overall poor quality of sleep. What's more, these disruptions become more common as we grow older. The clinical definition of insomnia varies, but studies estimate as much as 50% of the general population is suffering from the uncomfortable symptoms of insomnia.
There are many causes for sleep disruptions like noises, temperature (too hot or too cold), medication side effects, stress, depression, anxiety, pain/discomfort, food or caffeine (3). Cigarette smoking, irregular or inconsistent sleep patterns, and increased screen time with TV, video games, cell phones and tablets have also been shown to negatively affect how well we sleep (2). Some people turn to sleep aid medications or alcohol to help them sleep, but the side effects are often not desirable. Some people may also try solutions like hypnosis, meditation or cognitive behavior therapy (CBT), however, these can be expensive when working with a practitioner of these modalities.
How exercise can help you sleep better
There is substantial research supporting the role of exercise to help alleviate insomnia and sleep problems. Subjects in multiple studies report improved sleep quality and less often needing sleep aid medications following exercise sessions (4, 5). Interestingly, the greatest benefits of physical activity seem to be in people who have chronic sleep problems (6). Those who already have good sleep patterns may not notice sleep benefits from exercise.
In addition to improving sleep, adding exercise to the daily routine can also reduce depression symptoms, reduce plasma cortisol (a stress hormone), improve immune function and decrease tension and anxiety in people who are sedentary with chronic insomnia (7, 8).
But what if you consider yourself 'active' because you do a lot of housework or gardening, or because you walk or bike to work? It seems that doing household-related activity or lifestyle physical activity like commuting does not have the same benefits as recreational physical activity on improving sleep (9). And if you do get exercise, but also spend a lot of time sitting? It appears that greater sedentary time (particularly time sitting in front of the TV or computer) is associated with poorer sleep quality – even with high levels of physical activity (10, 11).
Why does exercise help us sleep better
There are many mechanisms proposed by researchers to explain why exercise may help improve sleep (12). It may be that the increase in core temperature as a result of exercise activates the heat dissipation mechanisms controlled by the hypothalamus. Exercise may also reduce anxiety, especially surrounding sleep, which people suffering from insomnia usually experience. Alternatively, some researchers suggest that because chronic insomnia may result from low serotonin activity, exercise increases brain serotonin, and thus helps to improve sleep.
Exercises to improve sleep quality
1. Engage in intentional recreational physical activity and exercise regularly.
2. Aerobic, interval training, yoga, tai chi or resistance exercise are all effective exercise modalities for improving sleep.
3. Minimize sedentary time sitting in front of the TV, computer, tablet, cell phone, etc.
4. Exercise any time of the day that you can.
5. Late afternoon or evening exercise generally does not negatively affect sleep (13), but if you find you sleep better when you exercise in the morning, do so!
Tips on how to sleep through the night
1. Keep consistent bedtimes and wake times every day – even on the weekends.
2. Cut back on caffeinated beverages especially in the afternoon.
3. Don't smoke.
4. Reduce or avoid screen time (TV, cell phone, tablet, computer) before bedtime.
5. Eliminate as much disruptive noise, lights and temperature fluctuations as possible.
6. Try a hot bath, warm beverages, meditation, massage, deep breathing or relaxing reading before bedtime (2).
To save these helpful tips, Pin This!
1. Mukherjee S, Patel SR, Kales SN, Ayas NT, Strohl KP, Gozal D, Malhotra A; American Thoracic Society ad hoc Committee on Healthy Sleep. An Official American Thoracic Society Statement: The Importance of Healthy Sleep. Recommendations and Future Priorities. Am J Respir Crit Care Med. 2015 Jun 15;191(12):1450-8.
2. Golem DL, Martin-Biggers JT, Koenings MM, Davis KF, Byrd-Bredbenner C. An integrative review of sleep for nutrition professionals. Adv Nutr. 2014 Nov 14;5(6):742-59.
3. Gerber M, Brand S, Holsboer-Trachsler E, Pühse U. Fitness and exercise as correlates of sleep complaints: is it all in our minds? Med Sci Sports Exerc. 2010 May;42(5):893-901.
4. Yang PY, Ho KH, Chen HC, Chien MY. Exercise training improves sleep quality in middle-aged and older adults with sleep problems: a systematic review. J Physiother. 2012;58(3):157-63.
5. Lang C, Kalak N, Brand S, Holsboer-Trachsler E, Pühse U, Gerber M. The relationship between physical activity and sleep from mid adolescence to early adulthood. A systematic review of methodological approaches and meta-analysis. Sleep Med Rev. 2016 Aug;28:32-45.
6. Oudegeest-Sander MH, Eijsvogels TH, Verheggen RJ, Poelkens F, Hopman MT, Jones H, Thijssen DH. Impact of physical fitness and daily energy expenditure on sleep efficiency in young and older humans. Gerontology. 2013;59(1):8-16.
7. Passos GS, Poyares D, Santana MG, Teixeira AA, Lira FS, Youngstedt SD, dos Santos RV, Tufik S, de Mello MT. Exercise improves immune function, antidepressive response, and sleep quality in patients with chronic primary insomnia. Biomed Res Int. 2014;2014:498961.
8. Passos GS, Poyares D, Santana MG, D'Aurea CV, Youngstedt SD, Tufik S, de Mello MT. Effects of moderate aerobic exercise training on chronic primary insomnia. Sleep Med. 2011 Dec;12(10):1018-27.
9. Kline CE, Irish LA, Krafty RT, Sternfeld B, Kravitz HM, Buysse DJ, Bromberger JT, Dugan SA, Hall MH. Consistently high sports/exercise activity is associated with better sleep quality, continuity and depth in midlife women: the SWAN sleep study. Sleep. 2013 Sep 1;36(9):1279-88.
10. Kakinami L, O'Loughlin EK, Brunet J, Dugas EN, Constantin E, Sabiston CM, O'Loughlin J. Associations between physical activity and sedentary behavior with sleep quality and quantity in young adults. Sleep Health. 2017 Feb;3(1):56-61.
11. Madden KM, Ashe MC, Lockhart C, Chase JM. Sedentary behavior and sleep efficiency in active community-dwelling older adults. Sleep Sci. 2014 Jun;7(2):82-8.
12. Passos GS, Poyares DL, Santana MG, Tufik S, Mello MT. Is exercise an alternative treatment for chronic insomnia? Clinics (Sao Paulo). 2012;67(6):653-60.
13. Buman MP, Phillips BA, Youngstedt SD, Kline CE, Hirshkowitz M. Does nighttime exercise really disturb sleep? Results from the 2013 National Sleep Foundation Sleep in America Poll. Sleep Med. 2014 Jul;15(7):755-61.